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Present value of lessee's discounted obligation for lease payments from finance lease.

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Total loss recognized during the period from the impairment of goodwill plus the loss recognized in the period resulting from the impairment of the carrying amount of intangible assets, other than goodwill.

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The number of states the entity operates in as of the balance sheet date.

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Represents the number of stores.

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Number of joint ventures. Joint ventures are entities operated by the controlling interest for the mutual benefit of the members.

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Operating lease remaining lease term.

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Percentage of service revenue.

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Summary of Significant Accounting Policies - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) Entity Store State	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Significant Accounting Policies [Line Items]
Number of joint ventures \| Entity	3
Allowance for doubtful accounts	$ 7,943	$ 6,503
Capitalized vendor rebates	12,007	11,603
Goodwill and intangible assets impairment	0	0	$ 0
Accrued sales returns	12,181	11,275
Selling, general and administrative expense	800,328	757,452	715,671
Finance lease ROU assets	3,150
Finance lease liabilities	3,231
Shipping and Handling [Member]
Significant Accounting Policies [Line Items]
Selling, general and administrative expense	54,783	51,741	47,670
Advertising Expense [Member]
Significant Accounting Policies [Line Items]
Selling, general and administrative expense	$ 16,587	$ 16,520	$ 24,677
Minimum [Member]
Significant Accounting Policies [Line Items]
Operating Lease Remaining Lease Term	1 year
Maximum [Member]
Significant Accounting Policies [Line Items]
Operating Lease Remaining Lease Term	10 years
Maximum [Member] \| Service Revenue Net [Member] \| Product Concentration Risk
Significant Accounting Policies [Line Items]
Percentage of revenue	1.00%	1.00%
Buildings and Improvements \| Minimum [Member]
Significant Accounting Policies [Line Items]
Estimated useful lives in years	3 years
Buildings and Improvements \| Maximum [Member]
Significant Accounting Policies [Line Items]
Estimated useful lives in years	40 years
Other Depreciable Assets \| Minimum [Member]
Significant Accounting Policies [Line Items]
Estimated useful lives in years	3 years
Other Depreciable Assets \| Maximum [Member]
Significant Accounting Policies [Line Items]
Estimated useful lives in years	10 years
Furniture and Fixtures \| Minimum [Member]
Significant Accounting Policies [Line Items]
Estimated useful lives in years	5 years
Furniture and Fixtures \| Maximum [Member]
Significant Accounting Policies [Line Items]
Estimated useful lives in years	7 years
Watsco, Inc.
Significant Accounting Policies [Line Items]
Number of locations from which entity operates \| Store	606
Number of states in which entity operates \| State	38